function addEvent(element, eventName, handler, phase) {
	if (window.addEventListener) {
		element.addEventListener(eventName, handler, phase);
	}

}

//简化读取/设置Cookie
var CookieUtil = {
	get : function(name) {
		var cookieName = decodeURIComponent(name) + "=", cookieStart = document.cookie
				.indexOf(cookieName), cookieValue = null;
		if (cookieStart > -1) {
			var cookieEnd = document.cookie.indexOf(";", cookieStart);
			if (cookieEnd == -1) {
				cookieEnd = document.cookie.length;
			}
			cookieValue = decodeURIComponent(document.cookie.substring(
					cookieStart + cookieName.length, cookieEnd));
		}
		return cookieValue;
	},
	set : function(name, value, expires, path, domain, secure) {
		var cookieText = encodeURIComponent(name) + "="
				+ encodeURIComponent(value);
		if (expires instanceof Date) {
			cookieText += "; expires=" + expires.toGMTString();
		}
		if (path) {
			cookieText += "; path=" + path;
		}
		if (domain) {
			cookieText += "; domain=" + domain;
		}
		if (secure) {
			cookieText += "; secure";
		}
		document.cookie = cookieText;
	},
	unset : function(name, path, domain, secure) {
		this.set(name, "", new Date(0), path, domain, secure);
	}
};
